Friction top can



June 22,1948. L. w. HILLS 2,443,984

v FRICTION TOP CAN Filed June 29, 1942 Patented June 22 1 948 Leslie WQHills, San Francisco, Calif., assignor to Hills Bros. Coifee,.Inc.,.San Francisco, Calif, a corporation of California Application June 29, 1942, Serial No. 448,931

. 11 Claims.

This invention relates larly directed to the: formation of a pryable hermetical seal as a closure for a container end and; which end may have two sealing connections in-. l

to pryable solder sealed tops for cans or containers, and is more particu the-range of the Vacuum of the order of 30 inches eluding a pryable soldered primary seal for the maintenance (of the contents of the can or container, and a secondary seal operable when the primary seal is broken to prevent rapid deteri-,

oration of the product contained within the can.

In the preservation of food products, particularly of the character susceptible to deterioration after opening as, for example, coffee, spices, paint, and other similar products which are generally retained in the can and used therefrom, there has long been sought some form of container which would enable the same to be sealed as it is packed, either under partial vacuum pressure, or the like, and which container would also provide a means which would permit its easy opening and at the same time provide a relatively tight coverproviding a secondary seal which would permit the cover to be removed and replaced after the breaking of the primary seal.

In such a container it is essential that the secondary seal permit of easy removal and replacing of the cover or closure member while providing a re-latively tight seal so that the contents of the can or container may be used therefrom easily and as desired.

I have found that I am able to form a primary seal for such a container which is easily broken by a prying action by forming a solder seal of limited width and which limited solder seal will withstand high internal pressures and high internal vacuulms alternately making the same particularly applicable for use as a container for products such as coffee and the like which are packed under high vacuum and then develop a relatively high internal pressure.

It is therefore an object of my invention to provide a sanitary can or containerhaving a cover member providing primary and secondary seals where the primary seal is of a permanent, enduring, and air-tightcharacteroperable to maintain the contents within the can and of the order necessary to. retain a vacuum or pressure, the secondary seal being of such character after destruction of the primary seal to protect the contents of the sanitary can.

Another object of my invention is to provide a,

friction top lid including an annular ring having mounted therein a friction top and between which friction top and annular ring there is provided a permanent seal which may be easily broken by a simple prying operation.

Another object of this invention is to provide a can end providing an hermetical seal which may be easily broken by a prying action and which is capable of withstanding alternate pressuresover of mercury and 20 pounds per square inch above atmospheric pressure.

Another object of my invention is to provide a top for a sanitary can which includes a primary and a secondary seal between the top or lid and an annular ring forming one end portion of such can, and which seals are of such character as to permit their being broken without mutilating or destroying the top or the annular ring.

Another object of this invention is to provide a friction top lid for a sanitary can having a solder seal of such confined area as to form an effective seal and yet which may be easily broken by a prying action, without requiring the use of a special form of prying tool.

Another. object of this invention is to provide the top and the annular ring of the end member of a sanitary can with annular flange means for the purpose of confining the area of the primary 1 seal formed between said top and annular ring.

Another object of this invention lies in the formation of the primary and secondary seals in such spaced relation as to avoid. adherence of the cooperating surfaces of the secondary seal lo cality of said primary seal and to prevent the solder fro'm flowing into said secondary'seal.

Other objects and advantages of this invention it is believed will be apparent from the following detailed description of a preferred embodiment thereof asillustrated in the accompanying drawings.

In the drawings:

Figure 1 is a perspective view of a sanitary can incorporating a friction top embodying my invention.

Figure 2 is a fragmental sectional view taken substantially on the line 22 of Figure 1.

Figure 3 is a view similar to Figure 2 of a modified form of structure embodying my invention.

Figure 4 is an enlarged fragmental sectional View in which the relative thicknesses are exaggerated for the purpose of illustration.

Figure 5 is a view similar to Figure 4 but being particularly applicable to the form of construction illustrated in Figure 3. i

In accordance with my invention, a sanitary can or other container l of any suitable or desirab le construction adapted to contain food or other material is provided with an end assembly 2.

As illustrated in Figures 1 and 2, the end'is a fabricated structure formed of sheet metal and consisting of an annular ring or wall part 3 and a friction top or cover part 4. Theend assembly 2 is formed in any suitable or desirable Way as is well understood in the art to enable the same to be rolled or crimped to the body of the container I as, for exampie, illustrated at 5. The particular manner or rolling of crimping the end 2 to the body I is commonly practiced in the art and for-ms no part of my invention.

The end assembly 2 is fabricated so as to p we vide between the annular ring 3 and the friction top 4 a primary seal 6 and a se'co'ntla'ry seal 1'. The entire end for the sanitary container 1 is preferably fabricated before the end is assembled or secured to the container I The annular ring 3 is formed at its outer edge to permit the fo-rrnae tion of the double sea-m and at its inner edge isprovided with a vertically extending annular flange '8' providing the "cylindrical surface 9, which defines the peripheral edge clan opening affordin'g access to the interior of the'oo-ntainei" "I.

Intermediate the inner and outer edges of the ring, the ring is tor-med in suchmanner as to provide a eon-lining area member in the term of a ridge or flange "It; iorth-etormationbf the friction top J n-nary seal '6. The formation of the ring 3, as illustrated in Figure 1, to provide a solder confinin'gfarea'rnemberor flange H] for the formation or the primary seal e, not only reinforces the ring, but also provides a more re stricted ib'l'fet "Sealing area at the apex of such flange. The raising of this sealing section also provides that the top 3 when secured in position to form the primaryseal will "be raised at its outer edge. flfawayironl the annular ring 3 sufiicieht to permit the asy insertion of a tool or instrument between the annular ring 3' and the flange II for p y ng the top t awa from the annular ring 3' to break the primary seal.

The fri ction top '4 is formed in any suitable or desirable manner to provide a complementary cylindrical surface 12 adapted" to =cooper'ate the cylindrical surface 9 to form a 'fi'ictionseal. These two complementary cylindrical surfaces form theseeohda'ry seal. The friction top -'4, utwardl'y from the cylindrical surface '9, is provided with the annular "fiange "i'l, which is preferably formed in such manner as to provide an annular confining area primary sealing section [3' overlyingthe primaryseal area provided by .the a ex of the flan e it orthe-annular ring. '3- This confining area is preferably formed in such manner as to reinforce the Range H at the point "of dormation of the primary seal so that a more'perf'ect sealing surface will be had. Theiorihat-ion of the confining section I 3 in the top '4 also. serves to straighten-out any waves or other 'va'riati'onspres ent in the material forming the top d prodil cing a soldering area plane limited by the oi the flange it whieh cooperates with the "sec tion {3- As-i'llus'trated in Figure 1, this reinforcingbl the annular flange II' is-prov'ided by deforming the flange in any suitable or desirable manner to form a channel 1-4 into which the compilemental-y vertical flange providingthe sealingsed tion I-ooi the annular ring 3 extends.

It will be evident that "the construction described for the-top or cover part l' includihg the lateral ofisetting' which forms the 'cyl'indricalsurfaoe 12-, serves to stiiien the cover a'gainst lateral bending. Likewise the o'ifse'tting which provides the flange 8 and ridge-like portion I0 serves to or desirable manner and then under the com bined influence of heat and pressure, fuse the I tinned surfaces together. For this purpose any ordinary or low temperature melting solders may I the secondary or friction seal 1 and is prevented from flowing into said secondary seal. By thus forming the primary seal, a pressure-tight seal is'mafmtained over the limited areas I0 and I3, which is easily broken by the prying action obtained from inserting a suitable tool such as the handle end of a common table spoon under the outwardly extending section of the flange I I and prying upwardly. This action will break the rimary seal and continued prying will force apart the secondary friction seal formed between the ezi' lintlrical surfaces 9 "and I2. Thus, the containei' maybe opened and when opened the desired quantity or material within the container may be removed and used as desired. The friction top "A may then be replaced, reestablishing the secondary seal which will re'du'ceto a minimum deterioration of the product contained within the container 1'.

The primary seal embodying my invention I have fouhd must be of limited character in order to permit'theseal to be broken easily by a simple rying actionas by inserting the end of a spoon or oth'erbluht instrument under the edge I I and prying upwardly over the rim of the 'c'on-tatner. A satisfactory term or such seal I have found is where the widthbf the radial in transverse crosssectional dimension of the annular solder seal is about "four tithes, or less, than the thickness of the shee't metal. can stock Of wl'l'ich-bhe top 4 TS formed. In practical prefer to employ. an annular solder seal which is about twice the thickness of the said stock, or for usein-aone=poundooffee 46 vacuu'inrpaokin'gof products such as 'cotfee, and

will likewise withstand the pressure whi'ch 'develops in such a container" which may develop to the; extentof approximately 20. poimds per sqiiarednchiabove amospheric' pres's'ure.

Itisrapparent that the primary'seal used for thislpiirpose must be able to withs'tandtlfisalternatepressureeondition to maintainthezcontents hermetically sealed under high vacuuman'd'have sufficient stren'g'th: tofprevent" any possibility of. the ower '4 being blown away' from the ring 2 when the relatively highpressure developst within the can.

WhilexI h'ave hereina'bove specified: the solder seal width'as being relatedto the thickness of. the sheet. metalastock used-in formirigthe top '4, it will "be appareht that s'uchsto'ok may-vary. 'This stock ordinarily enfploy'ed in one-pound cdffee cans a: thickness-of about @010. There 1s,

however, a definite relationship between the thickhess of the stock an'd the radialwidth 'of the solder seal having a definite relation'to the ability to pfythe to s-awa trom the ring 2. As the stoek decreases in thickness; it will be, necessary toreduce the width of the solder" seal because under such-circumstances the top 1 'as iorrn'ed ofi'sueh stock-would have less rigidity or resist-- ance to deformation under a prying action. As the thiokness'oi the stock increased, the thickness of the solder seal may iikeviisebe inereased without danger or the f-ricti'on to -becomingdestructime]? deformed or mutilated; 'lmfir a rying action. It is desirable to have a seal which will, however, open under a very slight prying action as long as that seal is effective to maintain the alternating pressure conditions as hereinabove specified.

In the second modification of my invention, as illustrated in Figure 3, similar parts are indicated by similar numerals with the addition of an exponent a thereto.

In this modification the annular ring 3a is formed substantially in the same manner as described in connection with the modification of my invention in Figures 1 and 2 with the exception that the primary seal flange or ridge Illa is formed with its sealing surface curved as illustrated at I5a. In this modification, the secondary seal la is illustrated as being formed in the same manner as in the first modification considered. The primary seal 6a is, however, formed also by forming the friction top 4a with a downwardly depending flange or ridge I 6a to provide a curved sealing area [3a immediately over the curved sealing area l5a of the annular ring 3a.

In this modification the material forming the peripheral annular flange Ila is doubled up on itself as at I'm to reinforce the annular flange and the cover 4d at the section adjacent the primary seal.

It will also be apparent from the foregoing description that one of the features of my invention is the forming of the primary seal 6 over a confined area as by flanging one or both of the parts of the assembly forming the primary seal to enable an accurate and reliable control of the width of the seal formed.

It is, of course, apparent that in the forming of the primary seal where solder is utilized the parts may be treated with a suitable flux prior to the sealing operation and it is also apparent that the cylindrical surfaces forming the secondary seal may be suitably treated to prevent the same from sticking together during the formation of the primary seal. These surfaces forming the friction seal may be efiectively protected against sticking together during the formation of the primary seal by lithographing one or both of the cooperating surfaces forming the secondary friction seal.

It will be apparent also that the can top and end may be made of any suitable material which, when properly treated, may be joined together by soldering.

Referring particularly to Figures 4 and 5, I have shown the solder seals as hereinabove set forth enlarged for the purpose of illustration, Figure'4 being the seal of the first modification of Figure 2, while Figure 5 is the cylindrical seal and modification illustrated in Figure 3. In Figure 4 the width of the limited end area formed by the flange or ridge i is of the order of twice the thickness of the sheet metal stock and the width of the solder seal is limited accordingly. In Figure the width of the limited end area of flange llla is of the order of four times the thickness of the sheet metal.

In these illustrations it will be observed that the solder seal S is limited by the area of the flange or flanges of the metal top and ring which cooperate in substantial contact. The end of the flange may thus be said to be a limiter of the width of the solder seal that may form the hermetical connection between the cover and ring.

Having fully described my invention, it is to be understood that I do not wish to be limited to the details herein set forth, but my invention is of the full scope of the appended claims.

I claim:

1. A container having a metallic member provided with an opening; a pryable top of a given thickness serving as a closure for said opening, said container portion having a raised ridge extending completely around said opening, said pryable top having a depending similar ridge disposed inwardly of its peripheral edge and in confronting relation to said first-mentioned ridge; and a readily frangible, circumferentially continuous solder connection between the apexes of said ridges providing an hermetic seal between said container portion and pryable top, said frangible connection being of a radial width of not more than about four times the thickness of the top material, said ridges spacing the edge of said pryable top from said container portion so that said edge can serve as a prying lip.

2. In a container construction wherein a sheet metal wall part of the container is provided with an opening for access into the interior of the con tainer, .a cover part formed of sheet metal and relatively rigid in resisting lateral bending, one of said parts being provided with a ridge-like circularly contoured offset which presents an end area to the other part of limited radial width, a continuous frangible solder seal between said end area and the other part and forming a hermetic seal for said opening, and means carried by the cover to enable prying of the same in a direction away from the wall part, said solder seal being a narrow and continuous line of solder of uniform width which is frangible throughout its length upon application of prying forces insufficient to cause substantial mutilation of the cover part.

3. In a container construction wherein a sheet metal wall part of the container is provided with :an opening for access into the interior of the container, a cover part formed of sheet metal, said cover part beingprovided with a ridge-like circularly contoured offset which presents an end area to the other part of limited radial width, a continuous frangible seal formed between said end area and the other part and forming a hermetic seal for said opening, and means carried by the cover to enable prying of the same in a direction away from the wall part, such seal being a narrow and continuous line of bonding material of uniform width which is frangible throughout its length upon application of prying forces insufficient to cause substantial mutilation of the cover part.

4. In a container construction wherein a sheet metal wall part of the container is provided with an opening for access into the interior of the container, a cover part formed of sheet metal, circularly contoured offsets formed on both the cover part and on the wall part, said offsets serving to stiffen said parts against lateral bending, one of said offsets being formed ridge-like to present an end area to the other offset which is of limited radial width, a continuous frangible seal between said end area and the other oifset and forming a hermetic seal for said opening, and means carried by the cover to enable prying of the same in a direction away from the wall part, said seal being a narrow and continuous line of bonding material of uniform width which is frangible throughout its length upon application of prying forces to the cover insufiicient to cause substantial mutilation of either the cover or wall parts.

5. In a container construction wherein a sheet:

metal wall part of the container is, provided with an opening for access into the interior of. the container, a cover part formed of sheet metal stiffened bylateral offsetting whereby it is relatively rigid in resisting lateral bending, the wallpart of the container being provided with lateral ofisetting whereby it is. relatively rigid. in resisting bending, one of said parts being provided with a ridge-like circularly contoured offset which presents an end area .to the other part of limited radial width, a continuous frangible solder seal between said end area and the, other part and forming .a hermetic seal for said opening, and means carried by the cover to enable prying of the same in a direction away from the wall part, said solder seal being a narrow and continuous lineof solder which is of a uniform width of not more than about four times the thickness of the sheet metal and is frangible throughout its. length upon application of prying forces to the cover insufficient to .causesubstantial mutilation of the same.

6.. In a container construction wherein a sheet metal wall part of the container is provided with an opening for access into the interior of the container, a cover part formed of sheet metal having an annular offset proportioned to have frictional; engagement with thevopening, said offset portion serving to stiffen the cover part against lateral bending, one of said parts being formed to provide another annular offset forming a ridge-and presenting an endarea to the other part which is of limited radial width, saidarea being spaced from said frictional engagement, a frangible solder seal between said areaiand the other part and forming a hermetic seal for said opening, and means carried by the cover to enable prying of the same in a direction away from the wall part, said solder seal being confined to a uniform width by the limited end area of said ridge. to provide a seal which is frangible throughout its length upon application of prying forces to the cover insufficient to cause substantial mutilation of the same, whereby said cover is frictionally engageable with said opening after breaking of said solder seal.

'1. Ina container construction wherein a sheet metal wall part of the container is provided with an opening for access into the interior of the container, a cover part formed of sheet metal provided with a circularly contoured offset serving to stiffen the same vagainst lateral bending, the wall part being provided with a circularly contoured offset forming the periphery of the opening and with which the offset portion of the cover is adapted to frictionallyengage, another circularly contoured ridge-like offset formed on one of the parts and presenting a relatively narrow circular end area to the other part, a frangible solder seal between said area and the other part and forming a hermetic seal about the opening, and means carried by theicover to enable prying of the same in a direction away from the cover, said solder seal being a narrow and continuous line of solder of uniform width not greater than about four times the thickness of the sheet metal and which is frangible throughout its length upon application of pryingforces insuflicien-t to cause substantial mutilation of the cover part.

8. In a container construction, a wall part formed of relatively bendable sheet metal having an opening for-access into the interior of the containerland provided with annular configurations about the opening to render said part relatively'rigid-said configurations including a ridge- 8 like annular offset providing an end areahaving an effective width of not more than about four times the thickness of the sheet metal, a cover part likewise formed of relatively bendable sheet metal, said cover part being configurated annularly to provide a relatively true annular planar sealing surface and to render the cover relatively rigid against deformation when pried from the wall part, said cover being provided with means serving to enable prying of the cover part in a direction away from the wall part of the container, and a hermetic solder seal between the end area of said ridge-like offset and said planar sealing surface of the cover part and forming a hermetic seal between said parts, said ,seal being limited in radial width by ,the width of the end area of said ridge to be readily frangible upon application of prying forces insuflicient to deform the cover and wall parts.

9. In a container construction wherein a sheet metal wall part of the container is provided with an opening for access into the interior of the container, a cover part formed of sheet metal stiffened by lateral offsetting to resist lateral bending, a ridge-like circularly contoured offset formed on one of said parts and surrounding the opening, said last named offset presenting a limited end face area to the other part which has a Width in a radial direction of the order of substantially twice the thicknessof the sheetmetal, a 'continuous'frangible solder seal formed between said. end face areaandthe other part and-forming a hermetic seal for said opening and means carried by the cover toenable pryingof the same in a direction away from the wall .part, said solder seal being frangible throughout its length upon application of prying forces insufficient to cause substantial mutilation of the coverpart.

10. In a container constructio-n wherein a-sheet metal wall partof the container is provided with an opening for access into the interior of the container, 9, cover part having an annular offset portion serving tostifien the same against lateral bending, the wall .part having an offset about the opening adapted to be frictionally engaged by the offset of the cover part, a ridge-like circularly contouredoifset formed on one of the parts and surrounding the opening, said last-named offset presenting a limited end face areato the other part which has a width in a radial direction of the order of not more than four times the thickness of the sheet metal, said end area being spaced from said frictional engagement, a continuous frangible connection between the end 7 area anclthe adjacentarea of the other part and forming a hermetic seal about the opening, the cover part having anedge portion spaced from the adjacent portion of the wall part by said ridge-like offset and forming means whereby the cover can be pried to break the entire length of the frangible connection and to remove the cover part from frictional engagement with the Wall part without substantial mutilation of either cover or wall parts.

11. In a container construction wherein a sheet metal wall part of the container is provided with an opening for access into the interior of the container and a friction-sealing surface surrounding the opening, a cover part formed of sheet metal and relatively rigid in resisting lateral bending, said cover part having a friction sealing surface for engaging said first named-sealing surface, one of said parts being provided with a ridge-like circularly contoured ofiset which presents in solderable proximity to the other part an end area of limited radial width, a continuous frangible solder seal between said end area and the other part and forming a hermetic seal for said opening, said seal being spaced from said friction sealing surface, and a flange carried by the cover to enable prying of the same in a direction away from the wall part, said solder seal being a narrow and continuous line of solder of uniform width which is frangible throughout its length upon application of prying forces insufiicient to cause substantial mutilation of the cover part, at least one of said friction sealing surfaces being lithographed to prevent sticking during formation of a solder seal.

LESLIE W. HILLS.

REFERENCES CITED The following references are of record in the file of this patent:

Number Punte July 14, 1942 Certificate of Correction Patent No. 2,443,984. June 22, 1948. LESLIE W. HILLS It is hereby certified that errors appear inthe above numbered patent requiring correction as follows: In the drawing, F

igures 2, 3, 4, and 5 should appear as shown below instead of as in the patent I column 4, line 40, for M, of an inch read of an inch read atmospheric; and that the said Letters Patent should b erem that the same may conform to the reco Signed and sealed this 23rd day of N ovem [snAL] THOMAS F. MURPHY,

Assistant Uommissioner of Patents. 

